neuromorphogenesis:

Training the brain to improve on new tasks

A brain-training task that increases the number of items an individual can remember over a short period of time may boost performance in other problem-solving tasks by enhancing communication between different brain areas. The new study being presented this week in San Francisco is one of a growing number of experiments on how working-memory training can measurably improve a range of skills – from multiplying in your head to reading a complex paragraph.

“Working memory is believed to be a core cognitive function on which many types of high-level cognition rely, including language comprehension and production, problem solving, and decision making,” says Brad Postle of the University of Wisconsin-Madison, who is co-chairing a session on working-memory training at the Cognitive Neuroscience Society (CNS) annual meeting today in San Francisco. Work by various neuroscientists to document the brain’s “plasticity” – changes brought about by experience – along with technical advances in using electromagnetic techniques to stimulate the brain and measure changes, have enabled researchers to explore the potential for working-memory training like never before, he says.

The cornerstone brain-training exercise in this field has been the “n-back” task, a challenging working memory task that requires an individual to mentally juggle several items simultaneously. Participants must remember both the recent stimuli and an increasing number of stimuli before it (e.g., the stimulus “1-back,” “2-back,” etc). These tasks can be adapted to also include an audio component or to remember more than one trait about the stimuli over time – for example, both the color and location of a shape.

Through a number of experiments over the past decade, Susanne Jaeggi of the University of Maryland, College Park, and others have found that participants who train with n-back tasks over the course of approximately a month for about 20 minutes per day not only get better at the n-back task itself, but also experience “transfer” to other cognitive tasks on which they did not train. “The effects generalize to important domains such as attentional control, reasoning, reading, or mathematical skills,” Jaeggi says. “Many of these improvements remain over the course of several months, suggesting that the benefits of the training are long lasting.”

As yet unresolved and controversial, however, has been understanding which factors determine whether working-memory training will generalize to other domains, as well as how the brain changes in response to the training. Work by Postle’s group using a new technique of applying electromagnetic stimulation on the brains of people undergoing working-memory training addresses some of these questions.

Training increases connectivity

Bornali Kundu of the University of Wisconsin-Madison, who works in Postle’s laboratory, used transcranial magnetic stimulation (TMS) with electroencephalography (EEG) to measure activity in specific brain circuits before and after training with an n-back task. “Our main finding was that training on the n-back task increased the number of items an individual could remember over a short period of time,” explains Kundu, who is presenting these new results today. “This increase in short-term memory performance was associated with enhanced communication between distant brain areas, in particular between the parietal and frontal brain areas.”

In the n-back task, Kundu’s team presented stimuli one-at-a-time on a computer screen and asked participants to decide if the current stimulus matched both the color and location of the stimulus presented a certain number of presentations previously. The color varied among seven primary colors, and the location varied among eight possible positions arranged in a square formation. The control task was playing the video game Tetris, which involves moving colored shapes to different locations, but does not require participants to remember anything. Before and after the training, researchers administered a range of cognitive tasks on which subjects did not receive training, and simultaneously delivered TMS while recording EEG, to measure communication between brain areas during task performance.

After practicing the n-back task for 5 hours a day and 5 days per week over 5 weeks, subjects were able to remember more items over short periods of time. Importantly, for those whose working memory improved, communication between the dorsolateral prefrontal cortex (DLPFC) and parietal cortex also improved. “This is in comparison to the control group, who showed no such differences in neural communication after practicing Tetris for 5 weeks,” Kundu says.

Working-memory training also produced improvement on cognitive tasks for which participants were not trained that are also believed to rely on communication between the parietal cortex and DLPFC. For two of these tasks – the ability to detect a change in a briefly presented array of squares, and the ability to detect a red letter “C” embedded in a field of distracting stimuli of rotated red “C”s and blue “C”s – those who had trained in the n-back test also showed a decrease in task-related EEG. The training exercise had registered a similar decrease. “The overall picture seems to be that the extent of transfer of training to untrained tasks depends on the overlap of neural circuits recruited by the two,” Kundu says.

Developing future therapies

Moving forward, many cognitive neuroscientists are working to see how working-memory training may specifically help clinical populations, such as patients with ADHD. “If we can learn the ‘rules’ that govern how, why, and when cognitive training can produce improvements that generalize to untrained tasks, it may be that therapies can be developed for patients suffering from neurological or psychiatric disease,” Postle says.

Both Jaeggi’s team, as well as Torkel Klingberg of the Karolinska Institute in Sweden, who is also presenting at the symposium today in San Francisco, have had success with such training for children with ADHD, decreasing the symptoms of inattention. “Here, the reason working-memory training may transfer to tests of fluid intelligence, as well as to a reduction in ADHD-associated hyperactivity symptoms, may be because both of those complex behaviors use some of the same brain circuits also used in performing the working-memory training tasks,” Kundu says.

“Individual differences in working memory performance have been related to individual differences in numerous real world skills such as reading comprehension, performance on standardized tests, and much more,” she adds. “I would not expect the same sorts of transfer effects that have been seen with working-memory training to happen if an individual practiced a task that used a minimally overlapping network, such as, for example, shooting three-pointers – which presumably uses different brain areas like primary and secondary motor cortex and the cerebellum.”

Jaeggi says that it is important to understand that cognitive abilities are not as unchangeable as some might think. “Even though there is certainly a hereditary component to mental abilities, that does not mean that there are not also components that are malleable and respond to experience and practice,” she says. “Whereas we try to strengthen participants’ working memory skills in our research, there are other routes that are possible as well, such as for example physical or musical training, meditation, nutrition, or even sleep.”

Despite all the promising research, Jaeggi says, researchers still need to understand many aspects of this work, such as “individual differences that influence training and transfer effects, the question of how long the effects last, and whether and how the effects translate into more real-world settings and ultimately, academic achievement.”

The symposium “The effects of working memory training on brain and behavior” takes place on April 15, 2013, at the 20th CNS annual meeting. More than 1,500 scientists are attending the meeting in San Francisco, CA, from April 13 to April 16, 2013.

neuromorphogenesis:

Ability to ‘think about thinking’ not limited to humans

Humans’ closest animal relatives, chimpanzees, have the ability to “think about thinking” – what is called “metacognition,” according to new research by scientists at Georgia State University and the University at Buffalo.

Michael J. Beran and Bonnie M. Perdue of the Georgia State Language Research Center (LRC) and J. David Smith of the University at Buffalo conducted the research, published in the journal Psychological Science of the Association for Psychological Science.

“The demonstration of metacognition in nonhuman primates has important implications regarding the emergence of self-reflective mind during humans’ cognitive evolution,” the research team noted.

Metacognition is the ability to recognize one’s own cognitive states. For example, a game show contestant must make the decision to “phone a friend” or risk it all, dependent on how confident he or she is in knowing the answer.

“There has been an intense debate in the scientific literature in recent years over whether metacognition is unique to humans,” Beran said.

Chimpanzees at Georgia State’s LRC have been trained to use a language-like system of symbols to name things, giving researchers a unique way to query animals about their states of knowing or not knowing.

In the experiment, researchers tested the chimpanzees on a task that required them to use symbols to name what food was hidden in a location. If a piece of banana was hidden, the chimpanzees would report that fact and gain the food by touching the symbol for banana on their symbol keyboards.

But then, the researchers provided chimpanzees either with complete or incomplete information about the identity of the food rewards.

In some cases, the chimpanzees had already seen what item was available in the hidden location and could immediately name it by touching the correct symbol without going to look at the item in the hidden location to see what it was.

In other cases, the chimpanzees could not know what food item was in the hidden location, because either they had not seen any food yet on that trial, or because even if they had seen a food item, it may not have been the one moved to the hidden location.

In those cases, they should have first gone to look in the hidden location before trying to name any food.

In the end, chimpanzees named items immediately and directly when they knew what was there, but they sought out more information before naming when they did not already know.

The research team said, “This pattern of behavior reflects a controlled information-seeking capacity that serves to support intelligent responding, and it strongly suggests that our closest living relative has metacognitive abilities closely related to those of humans.”

autistic-scientist:

There are thousands of receptor molecules on the surface of every cell in the body.  Each receptor is designed to seek out the complementary electron cloud from a receptor molecule.  When binding occurs, the stimulus is associated with the states of mind we could term “neuropeptides”.

It’s been agreed for quite some time that emotions are controlled within certain parts of the brain.  However, that’s an incomplete picture — because emotions are biochemical processes.  They are a function of these neuropeptides and the interactions between the various organs of the body.

Emotions occurs in the blood, the muscles, the tissues, and the bones — at the same time, and are then registered in the brain.  The limbic system transfers this information to the frontal cortex, where we then become conscious of the emotion.  It is only at this point that we begin to form ideas about what it is that we are feeling.  The experience itself occurs at a preconscious and physiological level, long before we become aware of what’s happening.

The vehicle that the mind and body use to communicate with each other is the chemistry of emotion.  All emotion is instigated and stored at a cellular level.  The “mind” is not stored in the brain — but throughout the whole body. 

The body is the subconscious mind and the brain is the conscious mind.  Information is stored in the DNA and concentrated in neuropeptieds at certain nodal points, which some have termed, the “chakrahs”.

Compassion meditation may boost neural basis of empathy

A compassion-based meditation program can significantly improve a person’s ability to read the facial expressions of others, finds a study published by Social Cognitive and Affective Neuroscience. This boost in empathic accuracy was detected through both behavioral testing of the study participants and through functional magnetic resonance imaging (fMRI) scans of their brain activity.

“It’s an intriguing result, suggesting that a behavioral intervention could enhance a key aspect of empathy,” says lead author Jennifer Mascaro, a post-doctoral fellow in anthropology at Emory University. “Previous research has shown that both children and adults who are better at reading the emotional expressions of others have better relationships.”

The meditation protocol, known as Cognitively-Based Compassion Training, or CBCT, was developed at Emory by study co-author Lobsang Tenzin Negi, director of the Emory-Tibet Partnership. Although derived from ancient Tibetan Buddhist practices, the CBCT program is secular in content and presentation.

(via neurosciencestuff)

ikenbot:

Lucid Dreamers Offer Clues to Consciousness

Lucid dreamers, people who can deliberately control their dreams during sleep, have long fascinated scientists. And now brain scans of those self-aware sleepers could offer insight into the seat of self-reflection in the mind.

It is difficult to get a full picture of what goes on in the brain when we make the transition from sleep to wakefulness. In fact, the specific areas of the brain underlying our restored self-perception and consciousness when we wake up have eluded scientists, according to a statement by the Max Planck Institute of Psychiatry. But a team of researchers was able to get a picture of that isolated activity in lucid dreamers.

“In a normal dream, we have a very basal consciousness, we experience perceptions and emotions but we are not aware that we are only dreaming,” study researcher Martin Dresler, of Max Planck, said in a statement. “It’s only in a lucid dream that the dreamer gets a meta-insight into his or her state.”

Using functional magnetic resonance imaging (fMRI) brain scans, the team compared the activity of the brain during one of these lucid-dreaming periods with the activity just beforehand in a normal dream. Out of four participants, only two lucid-dreaming episodes could be verified as lucid dreams and were long enough to analyze with fMRI, which measures blood flow to brain regions in real time; an increase in blood flow to a specific region is a sign that region is becoming more active.

The results, detailed online July 1 in the journal Sleep, showed that a specific cortical network is activated when lucid consciousness is attained. Michael Czisch, another Max Planck researcher involved in the study, said activity in certain areas of the cerebral cortex spikes within seconds when a lucid state begins.

These regions include the right dorsolateral prefrontal cortex, which has previously been associated with self-assessment, and the frontopolar regions, where the act of evaluating our own thoughts and feelings takes place, Czisch explained in a statement. “The precuneus is also especially active, a part of the brain that has long been linked with self-perception,” he said.

Previous research at the Max Planck Institute compared the brain activity of lucid dreamers as they entertained the same thoughts while awake and asleep. The brain activity was similar, if weaker during sleep, the researchers found.

Ecstasy Harms Memory With One Year of Recreational Use

New research published online July 25 by the scientific journal Addiction, gives some of the first information available on the actual risk of using ecstasy. It shows that even in recreational amounts over a relatively short time period, ecstasy users risk specific memory impairments. Further, as the nature of the impairments may not be immediately obvious to the user, it is possible people wouldn’t get the signs that they are being damaged by drug use until it is too late.

According to the study, new ecstasy users who took ten or more ecstasy pills over their first year of use showed decreased function of their immediate and short-term memory compared with their pre-ecstasy performance. These findings are associated with damage of the hippocampus, the area of the brain that oversees memory function and navigation. Interestingly, hippocampal damage is one of the first signs of Alzheimer’s disease, resulting in memory loss and disorientation.

ikenbot:

Do Psychedelics Expand the Mind by Reducing Brain Activity?

What would you see if you could look inside a hallucinating brain?

New evidence suggests drugs like LSD open the doors of perception by inhibiting parts of the brain

Despite decades of scientific investigation, we still lack a clear understanding of how hallucinogenic drugs such as LSD (lysergic acid diethylamide), mescaline, and psilocybin (the main active ingredient in magic mushrooms) work in the brain.

Modern science has demonstrated that hallucinogens activate receptors for serotonin, one of the brain’s key chemical messengers. Specifically, of the 15 different serotonin receptors, the 2A subtype (5-HT2A), seems to be the one that produces profound alterations of thought and perception. It is uncertain, however, why activation of the 5-HT2A receptor by hallucinogens produces psychedelic effects, but many scientists believe that the effects are linked to increases in brain activity.

Although it is not known why this activation would lead to profound alterations of consciousness, one speculation is that an increase in the spontaneous firing of certain types of brain cells leads to altered sensory and perceptual processing, uncontrolled memory retrieval, and the projection of mental “noise” into the mind’s eye.

The English author Aldous Huxley believed that the brain acts as a “reducing valve” that constrains conscious awareness, with mescaline and other hallucinogens inducing psychedelic effects by inhibiting this filtering mechanism. Huxley based this explanation entirely on his personal experiences with mescaline, which was given to him by Humphrey Osmond, the psychiatrist who coined the term psychedelic. Even though Huxley proposed this idea in 1954, decades before the advent of modern brain science, it turns out that he may have been correct. Although the prevailing view has been that hallucinogens work by activating the brain, rather than by inhibiting it as Huxley proposed, the results of a recent imaging study are challenging these conventional explanations.

The study in question was conducted by Dr. Robin Carhart-Harris in conjunction with Professor David Nutt, a psychiatrist who was formerly a scientific advisor to the UK government on drugs policy. Drs. Carhart-Harris, Nutt, and colleagues used functional magnetic resonance imaging (fMRI) to study the effects of psilocybin on brain activity in 30 experienced hallucinogen users. In this study, intravenous administration of 2 mg of psilocybin induced a moderately intense psychedelic state that was associated with reductions of neuronal activity in brain regions such as the medial prefrontal cortex (mPFC) and the anterior cingulate cortex (ACC).

The mPFC and ACC are highly interconnected with other brain regions and are believed to be involved in functions such as emotional regulation, cognitive processing, and introspection. Based on their findings, the authors of the study concluded that hallucinogens reduce activity in specific “hub” regions of the brain, potentially diminishing their ability to coordinate activity in downstream brain regions. In effect, psilocybin appears to inhibit brain regions that are responsible for constraining consciousness within the narrow boundaries of the normal waking state, an interpretation that is remarkably similar to what Huxley proposed over half a century ago.

ikenbot:

Artificial Intelligence Could Be on Brink of Passing Turing Test

One hundred years after Alan Turing was born, his eponymous test remains an elusive benchmark for artificial intelligence. Now, for the first time in decades, it’s possible to imagine a machine making the grade.

Turing was one of the 20th century’s great mathematicians, a conceptual architect of modern computing whose codebreaking played a decisive part in World War II. His test, described in a seminal dawn-of-the-computer-age paper, was deceptively simple: If a machine could pass for human in conversation, the machine could be considered intelligent.

Artificial intelligences are now ubiquitous, from GPS navigation systems and Google algorithms to automated customer service and Apple’s Siri, to say nothing of Deep Blue and Watson — but no machine has met Turing’s standard. The quest to do so, however, and the lines of research inspired by the general challenge of modeling human thought, have profoundly influenced both computer and cognitive science.

There is reason to believe that code kernels for the first Turing-intelligent machine have already been written.

“Two revolutionary advances in information technology may bring the Turing test out of retirement,” wrote Robert French, a cognitive scientist at the French National Center for Scientific Research, in an Apr. 12 Science essay. “The first is the ready availability of vast amounts of raw data — from video feeds to complete sound environments, and from casual conversations to technical documents on every conceivable subject. The second is the advent of sophisticated techniques for collecting, organizing, and processing this rich collection of data.”

Read on..

laboratoryequipment:

Gray Matter Linked to Decision-Making Process

The more gray matter you have in the decision-making, thought-processing part of your brain, the better your ability to evaluate rewards and consequences. That may seem like an obvious conclusion, but a new study conducted at the U.S. Department of Energy’s Brookhaven National Laboratory is the first to show this link between structure and function in healthy people—and the impairment of both structure and function in people addicted to cocaine. The study appears in the Journal of Cognitive Neuroscience.

Read more: http://www.laboratoryequipment.com/news-Gray-Matter-Linked-to-Decision-Making-Process-112611.aspx